1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2012 Samsung Electronics
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <sys/stat.h>
#include <compiler.h>
#define CHECKSUM_OFFSET (14*1024-4)
#define FILE_PERM (S_IRUSR | S_IWUSR | S_IRGRP \
| S_IWGRP | S_IROTH | S_IWOTH)
/*
* Requirement for the fixed size SPL header:
* IROM code reads first (CHECKSUM_OFFSET + 4) bytes from boot device. It then
* calculates the checksum of CHECKSUM_OFFSET bytes and compares with data at
* CHECKSUM_OFFSET location.
*
* Requirement for the variable size SPL header:
* IROM code reads the below header to find out the size of the blob (total
* size, header size included) and its checksum. Then it reads the rest of the
* blob [i.e size - sizeof(struct var_size_header) bytes], calculates the
* checksum and compares it with value read from the header.
*/
struct var_size_header {
uint32_t spl_size;
uint32_t spl_checksum;
uint32_t reserved[2];
};
static const char *prog_name;
static void write_to_file(int ofd, void *buffer, int size)
{
if (write(ofd, buffer, size) == size)
return;
fprintf(stderr, "%s: Failed to write to output file: %s\n",
prog_name, strerror(errno));
exit(EXIT_FAILURE);
}
/*
* The argv is expected to include one optional parameter and two filenames:
* [--vs] IN OUT
*
* --vs - turns on the variable size SPL mode
* IN - the u-boot SPL binary, usually u-boot-spl.bin
* OUT - the prepared SPL blob, usually ${BOARD}-spl.bin
*
* This utility first reads the "u-boot-spl.bin" into a buffer. In case of
* fixed size SPL the buffer size is exactly CHECKSUM_OFFSET (such that
* smaller u-boot-spl.bin gets padded with 0xff bytes, the larger than limit
* u-boot-spl.bin causes an error). For variable size SPL the buffer size is
* eqaul to size of the IN file.
*
* Then it calculates checksum of the buffer by just summing up all bytes.
* Then
*
* - for fixed size SPL the buffer is written into the output file and the
* checksum is appended to the file in little endian format, which results
* in checksum added exactly at CHECKSUM_OFFSET.
*
* - for variable size SPL the checksum and file size are stored in the
* var_size_header structure (again, in little endian format) and the
* structure is written into the output file. Then the buffer is written
* into the output file.
*/
int main(int argc, char **argv)
{
unsigned char *buffer;
int i, ifd, ofd;
uint32_t checksum = 0;
off_t len;
int var_size_flag, read_size, count;
struct stat stat;
const int if_index = argc - 2; /* Input file name index in argv. */
const int of_index = argc - 1; /* Output file name index in argv. */
/* Strip path off the program name. */
prog_name = strrchr(argv[0], '/');
if (prog_name)
prog_name++;
else
prog_name = argv[0];
if ((argc < 3) ||
(argc > 4) ||
((argc == 4) && strcmp(argv[1], "--vs"))) {
fprintf(stderr, "Usage: %s [--vs] <infile> <outfile>\n",
prog_name);
exit(EXIT_FAILURE);
}
/* four args mean variable size SPL wrapper is required */
var_size_flag = (argc == 4);
ifd = open(argv[if_index], O_RDONLY);
if (ifd < 0) {
fprintf(stderr, "%s: Can't open %s: %s\n",
prog_name, argv[if_index], strerror(errno));
exit(EXIT_FAILURE);
}
ofd = open(argv[of_index], O_WRONLY | O_CREAT | O_TRUNC, FILE_PERM);
if (ofd < 0) {
fprintf(stderr, "%s: Can't open %s: %s\n",
prog_name, argv[of_index], strerror(errno));
exit(EXIT_FAILURE);
}
if (fstat(ifd, &stat)) {
fprintf(stderr, "%s: Unable to get size of %s: %s\n",
prog_name, argv[if_index], strerror(errno));
exit(EXIT_FAILURE);
}
len = stat.st_size;
if (var_size_flag) {
read_size = len;
count = len;
} else {
if (len > CHECKSUM_OFFSET) {
fprintf(stderr,
"%s: %s is too big (exceeds %d bytes)\n",
prog_name, argv[if_index], CHECKSUM_OFFSET);
exit(EXIT_FAILURE);
}
count = CHECKSUM_OFFSET;
read_size = len;
}
buffer = malloc(count);
if (!buffer) {
fprintf(stderr,
"%s: Failed to allocate %d bytes to store %s\n",
prog_name, count, argv[if_index]);
exit(EXIT_FAILURE);
}
if (read(ifd, buffer, read_size) != read_size) {
fprintf(stderr, "%s: Can't read %s: %s\n",
prog_name, argv[if_index], strerror(errno));
exit(EXIT_FAILURE);
}
/* Pad if needed with 0xff to make flashing faster. */
if (read_size < count)
memset((char *)buffer + read_size, 0xff, count - read_size);
for (i = 0, checksum = 0; i < count; i++)
checksum += buffer[i];
checksum = cpu_to_le32(checksum);
if (var_size_flag) {
/* Prepare and write out the variable size SPL header. */
struct var_size_header vsh;
uint32_t spl_size;
memset(&vsh, 0, sizeof(vsh));
memcpy(&vsh.spl_checksum, &checksum, sizeof(checksum));
spl_size = cpu_to_le32(count + sizeof(struct var_size_header));
memcpy(&vsh.spl_size, &spl_size, sizeof(spl_size));
write_to_file(ofd, &vsh, sizeof(vsh));
}
write_to_file(ofd, buffer, count);
/* For fixed size SPL checksum is appended in the end. */
if (!var_size_flag)
write_to_file(ofd, &checksum, sizeof(checksum));
close(ifd);
close(ofd);
free(buffer);
return EXIT_SUCCESS;
}
|
